1. Field of the Invention
The present invention relates to an edger, and, more particularly, to an edger used for trimming the edge of a lawn and a grass along the road or curbstones.
2. Prior Art
A conventional edger has been arranged to have a rotary blade operated by an engine and disposed in the front portion on either side of the edger body and runs with its front and the rear wheels grounded. The edging operation is performed not only in a flat area but also, for example, along curbstones disposed to some extent higher than the level ground. Since the width of the curbstone structure is usually smaller than that of the edger, the wheel disposed on the opposite side to the rotary blade projects over the curbstones and floats. In this case, an operator must conduct the edging operation with a portion of the edger projecting over the supporting curbstones, causing hard labor. What is worse, the result of the edging operation usually becomes unsatisfactory.
Accordingly, the conventional structure has been arranged in such a manner that an attachment to which a wheel is fastened to a junction of a V-shaped frame thereof is, via a sub-frame and a bolt, fastened to the rear wheel positioned opposite to the rotary blade of the edger body. Thus, the wheel fastened to the attachment is grounded on a flat area B (as indicated in FIG. 7) below the curbstones so that the side portion of the edger projecting over the curbstones is supported. Thus, the edger can be properly leveled at the time of the edging operation.
Another edger (an example of which is illustrated in FIG. 8) has been known which is arranged in such a manner that a rear wheel disposed opposite to the rotary blade of the edger body is, via a supporting plate, disposed at the lower end portion of a vertical position adjusting plate in the form of a sector. Furthermore, the central portion of the sector vertical position adjusting plate is rotatably borne on the edger body. In addition, a plurality of through-holes are formed in the circumferential direction of the position adjusting plate at certain intervals and a supporting member having a threaded hole formed therein is arranged to project over the edger body. A bolt inserted into one of the above-described through-holes is inserted into the threaded hole so that the above-described position adjusting plate is fixed. The vertical position of the rear wheel with respect to the edger body can be adjusted by changing the through-hole formed in the position adjusting plate into which the above-described bolt is inserted. An example of the above-described conventional technology has been disclosed in Japanese Utility Model Laid-Open No. 62-99937.
According to the above-described two conventional edgers, a user must temporarily release the handle of the edger so as to fasten the attachment with a bolt or change the through hole formed in the position adjusting plate into which the bolt is inserted. Therefore, the operation takes excessively long. Furthermore, the adjustment of the vertical position of the above-described wheel (the rear wheel) with respect to the edger body must be conducted with the edger body supported from the side direction (the opposite side to the rotary blade). Therefore, it is difficult to complete the adjustment work. In particular, the former edger raises the necessity to reserve the attachment when it is not used, causing difficulties.